kevinhooke

sls invoke local --function functionname

NoSuchMethodError: 'void com.amazonaws.services.lambda.runtime.LambdaLogger.log ...

Per https://github.com/serverless/serverless/issues/5155
change aws-lambda-java-log4j2 verion in pom.xml to 1.0.0

kevinhooke

Primary keys - 2 types:

- Partition key: unique value, internally is hashed to determine which partition item is stored in

- Partition and sort key: composite key of an id and an attribute that sorts items by this value
  - sort key is also called a range attribute
  - the combination of partition id and sort key must be unique, but partition id can exist for multiple rows
  - allows storing multiple rows for a specific id, for example:
if employeeid = partition key and employee_info = sort key
employeeid=1, employee_info=contactinfo

kevinhooke

- a module can only have one default export:
export default A = //something

... and can be imported with any name:
import A from './A.js';
import B from './A.js';
import someothername from './A.js'


- named exports are imported by their exact name only, a module can have zero, one or more named exports

kevinhooke

# diff changed files against previous commit - this doesn't show anything for a first commit
git diff-tree --no-commit-id --name-only -r commithash

# list all files on a commit
git ls-tree --name-only -r commithash

# delete a file from all commit history
git filter-branch --tree-filter "rm -f filename" HEAD

kevinhooke

React fragments https://reactjs.org/docs/fragments.html
- group a list of child elements without grouping them wihin a containing parent element in the DOM where that
would be invalid. An example is a list of <td> elements rendered by a component. If the parent component renders a <tr>,
if the child element wrapped these in a <div> that would be invald HTML structure, but they can be logically grouped
as a fragment instead, using <React.Fragrment>, or the <> </> JSX shorthand

React Context: https://reactjs.org/docs/context.html
- used to automatically pass props down to all child elements without passing the props manually from one child to the next

kevinhooke

Fast Forward
- when no other changes made to master between the last change and the change you are about to merge on your branch, 
master is 'fast forwarded' to point to your last commit that you are merging into master (no other changes to merge)

Merging a branch
- checkout target branch: git checkout targetname
- merge source into the target: git merge sourcename

kevinhooke

# switch branches
git branch branchname

# chekout files on branch
git checkout branchname

# both of the above combined
git checkout -b branchname

#rename a branch

kevinhooke

JAX-RS Jersey                           Spring RestController
-------------                           ---------------------
@Path("/examplepath")                   @RestController
                                        @RequestMapping("/examplepath")
                        
@GET("/item")                           @GetMapping("/item")
@Produces(MediaType.APPLICATION_JSON)

@QueryParam("id")                       @RequestParam("id") // e.g. /example?id=123
@PathParam("id")                        @PathVariable("id") //e.g. /example/{id}/detail

kevinhooke

Edit ~/.ssh/config and for each repo add the following block:

host hostname-of-repo
  user your-id-for-this-repo
  identityfile ~/.ssh/filename-of-key

kevinhooke

aws --endpoint-url=http://localhost:4566 dynamodb put-item --table-name exampletable --item '{
    "LastName" : { "S" : "test1" }
  }' \
  --return-consumed-capacity TOTAL

#query table with only a hash key
aws --endpoint-url=http://localhost:4566 dynamodb query --table-name exampletable \
    --key-condition-expression "LastName = :v1" \
    --expression-attribute-values '{
      ":v1" : {"S": "test1"}